Meet Shining Wish, one of my newest MLP:FIM's OCs. She a mature young mare who works as a veterinary with her younger sister Heavy.

She came from an long line of unicorns family, which she was their main star. When her sister Heavy born, she was really happy with the arrival of her little sister, but her parents, well, they were extremely disappointed with the fact that Heavy was born an pegasus instead of an unicorn. The little pegasus could ruin their reputation of pure unicorns, so they kept her as a secret from everyone untill she got old enough for them to do something about her. Shining Wish never understood why her parents wouldn't let her play with her sister, nor even talk to her, everynight she went to her room without nobody notice so they could talk and play games. When she was a little bit more than a filly her parents decided that it was time to deal with their "pegasus problem" and were going to send her alone to live with her grandaunt (who Wish didn't even know that existed before that day), but for Wish, if her sister was going to live in another place, so did her. Her parents were reluctant to sent their little jewel away but they also couldn't stay with Heavy.
Both fillies were sent to live with their grandaunt, and only then she understood why nobody had told her about her grandaunt: she was an pegasus. Unfortunately, their grandaunt died not too long after they started living together, leaving Wish and Heavy alone in the world since she wouldn't come back to the ponies who were able to hid their daughter and sent her to live far away just because she was a pegasus.

While she was growing up, may stallions tried to win her heart, she even liked some of them, but as soon as she presented her sister to them they showed their true side. Ponies who would laugh of someone just because she was different. She soon gave up loving and decided to live to take care of her sister and to help animals, becoming a veterinary.

Sorry for the bad spelling or/and grammar!